[mojo] Use base::Pickle for Message storage.
This CL modifies the mojo::Message implementation so that
its storage is always backed by a base::Pickle.
Part of a series of changes to support custom mojom serialization:
1. https://codereview.chromium.org/1515423002
2. https://codereview.chromium.org/1517043004
3. https://codereview.chromium.org/1524693002
4. https://codereview.chromium.org/1520153002
5. This CL
6. https://codereview.chromium.org/1526533002
7. https://codereview.chromium.org/1524703002
BUG=569669
Review URL: https://codereview.chromium.org/1524613002
Cr-Commit-Position: refs/heads/master@{#365766}
diff --git a/base/pickle.h b/base/pickle.h
index 72b33ddc..8e82c62 100644
--- a/base/pickle.h
+++ b/base/pickle.h
@@ -258,6 +258,13 @@
// of the header.
void Resize(size_t new_capacity);
+ // Claims |num_bytes| bytes of payload. This is similar to Reserve() in that
+ // it may grow the capacity, but it also advances the write offset of the
+ // pickle by |num_bytes|. Claimed memory, including padding, is zeroed.
+ //
+ // Returns the address of the first byte claimed.
+ void* ClaimBytes(size_t num_bytes);
+
// Find the end of the pickled data that starts at range_start. Returns NULL
// if the entire Pickle is not found in the given data range.
static const char* FindNext(size_t header_size,
@@ -299,6 +306,8 @@
WriteBytesStatic<sizeof(data)>(&data);
return true;
}
+
+ inline void* ClaimUninitializedBytesInternal(size_t num_bytes);
inline void WriteBytesCommon(const void* data, size_t length);
FRIEND_TEST_ALL_PREFIXES(PickleTest, DeepCopyResize);
